The present invention relates to an information processing device, information recording medium, information processing method, and computer program. More particularly, the present invention relates to an information processing device, information recording medium, information processing method, and computer program, for preventing playback interruption due to jump processing at the time of playback of recorded contents on a disc, thereby enabling seamless content playback.
Various types of software data, such as audio data like music and so forth, image data like movies and so forth, game programs, various types of application programs, and so forth, can be stored in recording media, e.g., discs such as Blu-ray discs applying blue laser, DVDs (Digital Versatile Disc), and so forth.
Data storage formats are stipulated corresponding to each of the various types of data, and each data is stored according to its respective format.
For example, in the event of performing playback of contents having a data recording configuration such that image data and audio data are stored separately on a disc, or multi-angle contents configured of image data from various angles, there is the need to jump between data recording regions that are away from one another on the disc, to read the necessary data for playing thereof.
In the reading and playing processing of contents stored in a disc, the procedures of
obtaining information from the disc,
temporary storage (buffering) of the obtaining information,
decoding/decryption of buffer data, and
output of data following decoding,
are executed.
Decoding/decryption of buffer data includes decoding processing of MPEG data in the event that the contents are MPEG data for example, and decryption of encrypted data in the event that the data is encrypted.
In the event that data, regarding which consecutive playing should be performed, is at positions with distance therebetween, the reading head needs to move, i.e., jump processing needs to be performed. In the event of jump processing occurring, time is required for performing jump processing from a data play position on the disc to a position which is distanced therefrom, to read the data at the next read position and perform play processing. In the event that this time is long, there are cases wherein play interruption can occur. For example, in the Patent Document 1 mentioned below, data is recorded in sections, for a case taking into consideration a case of jumping without playing a certain block, taking into consideration the capacity of buffer memory, the speed of track jumping, rotation wait time, and ECC block processing time. However, whether or not there is encoding/encryption is not described, nor is there any consideration given to cases wherein different encryption keys are used for each block. Moreover, in the case of parental lock, a few particular paths may be traveled, but in the case of identifying equipment used to create unauthorized copies, a great number of paths need to be prepared, and from this perspective as well, consecutive playback will be difficult unless there is some consideration given to a special data placement for performing consecutive playing.
Patent Document 1 Japanese Unexamined Patent Application Publication No. 9-274769